American Society of Hematology 2018 guidelines for management of venous thromboembolism: optimal management of anticoagulation therapy

Care pathway for patients hospitalized with venous thromboembolism

BACKGROUND

Venous thromboembolism (VTE), including pulmonary embolism (PE) and deep vein thrombosis (DVT), is a potentially fatal disease with a multifactorial nature, impacting different medical and surgical specialties. Recently, new guidelines and direct oral anticoagulants facilitated early discharge for most DVT patients and non-severe PE patients.

OBJECTIVE

The aim of this study is to illustrate the distribution of VTE patients throughout the hospital and map their care pathway from Emergency Department (ED) to hospital discharge.

METHODS

This multicenter retrospective cross-sectional study included all hospitalized patients with a VTE code from 39 hospitals between 2018 and 2019. Data were analysed using JupyterLab, with subgroup analyses based on mode of entry, diagnosis location and thrombosis site.

RESULTS

A total of 23,199 hospitalizations were analysed, involving 17,718 patients a median age 66 years [52-78] and man-to-women ratio 1.05. Among these, 10,747(46.3%) had PE and 4176(18.0%) had lower limb DVT. The ED was the primary entry point for 31.2% of cases, followed by gastroenterology, surgery, geriatrics, and internal medicine. Patients admitted through ED patients were most frequently transferred to internal medicine, cardiovascular and intensive care units (ICU). The median hospital stay was 9 days [4-21], with ICU stays being the longest (mean 15 days [8-27]). Notably, 1357 patients (18.8%) of VTE patients were discharged within 48 h of ED admission.

CONCLUSIONS

This study is the first to portray the distribution and care pathways of VTE patients across hospital departments. Despite recent clinical guidelines, many patients still require inpatient management, highlighting the need for dedicated care pathway.

Rivaroxaban for 18 Months Versus 6 Months in Patients With Cancer and Acute Low-Risk Pulmonary Embolism: An Open-Label, Multicenter, Randomized Clinical Trial (ONCO PE Trial)

BACKGROUND

The optimal duration of anticoagulation therapy for patients with cancer and acute low-risk pulmonary embolism (PE) is clinically relevant, but evidence is lacking. Prolonged anticoagulation therapy could have a potential benefit for prevention of thrombotic events; however, it could also increase the risk of bleeding.

METHODS

In a multicenter, open-label, adjudicator-blinded, randomized clinical trial at 32 institutions in Japan, we randomly assigned patients with cancer and acute low-risk PE of the simplified version of the Pulmonary Embolism Severity Index score of 1, in a 1:1 ratio, to receive either an 18-month or a 6-month rivaroxaban treatment. The primary end point was recurrent venous thromboembolism (VTE) at 18 months. The major secondary end point was major bleeding at 18 months according to the criteria of the International Society on Thrombosis and Hemostasis. The primary hypothesis was that an 18-month treatment was superior to a 6-month treatment in terms of the primary end point.

RESULTS

From February 2021 to March 2023, 179 patients were randomized, and after the exclusion of one patient who withdrew consent, 178 were included in the intention-to-treat population: 89 patients in the 18-month rivaroxaban group and 89 in the 6-month rivaroxaban group. The mean age was 65.7 years; 47% of the patients were men, and 12% had symptoms of PE at baseline. The primary end point of recurrent VTE occurred in 5 of the 89 patients (5.6%) in the 18-month rivaroxaban group and in 17 of the 89 (19.1%) in the 6-month rivaroxaban group (odds ratio, 0.25 [95% CI, 0.09-0.72]; P=0.01). Among 22 recurrent VTE, 5 patients presented with a symptomatic recurrent VTE; recurrent PE occurred in 11 patients, including 2 with main and 4 with lobar PEs; and recurrent deep vein thrombosis was seen in 11 patients, including 3 with proximal deep vein thromboses. The major secondary end point of major bleeding occurred in 7 of the 89 patients (7.8%) in the 18-month rivaroxaban group and in 5 of the 89 patients (5.6%) in the 6-month rivaroxaban group (odds ratio, 1.43 [95% CI, 0.44-4.70]; P=0.55).

CONCLUSIONS

In patients with cancer and acute low-risk PE of the simplified version of the Pulmonary Embolism Severity Index score of 1, the 18-month rivaroxaban treatment was superior to the 6-month rivaroxaban treatment with respect to recurrent VTE events.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT04724460.

Therapeutic Enoxaparin Dosing in Obesity

OBJECTIVE

This review aims to systematically summarize the available data on efficacy and safety of therapeutic enoxaparin in obese patients and to identify gaps to guide future research.

DATA SOURCES

Medline and Embase were systematically searched for eligible studies (last searched December 20, 2023). Studies were included if they reported on therapeutic dosing regimens, adverse bleeding, thrombotic outcomes, or antifactor Xa (AFXa) monitoring in obese adult patients.

STUDY SELECTION AND DATA EXTRACTION

The systematic review management tool Covidence was used to manage the study selection and data extraction process. The reference list from eligible studies was screened to determine any additional eligible studies.

DATA SYNTHESIS

Sixteen studies were included in the analysis. Studies used a variety of doses, indications, and study designs making comparison difficult. Twelve studies reported the incidence of thrombotic events (median = 1.3% [interquartile range [IQR] = 0.3%-2.3%]) and all studies reported the incidence of bleeding events (median = 5.7% [IQR = 2.4%-14.5%]). Two of the 8 studies analyzing the influence of weight/body mass index (BMI) or dose per kg on AFXa levels reported statistically significant results. One study concluded that BMI did not affect achievement of target AFXa levels. However, the second study found that dosing using actual body weight was an independent predictor of supratherapeutic AFXa levels in the obese population.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

This is the first comprehensive review with a focus on therapeutic dosing of enoxaparin in obesity and has been conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 statement. Seven of the included studies were published since 2018 indicating that new evidence on this topic is emerging.

CONCLUSION

There was inadequate evidence to support an optimal dosing strategy in obese patients due to the heterogeneity of the studies. The AFXa monitoring may be appropriate to guide dosing in this population. Further research is required to determine a suitable dosing regimen.

Validation of a whole blood coagulometer sensitive to the direct oral anticoagulants

Readily available and rapid turn-around, bedside assays to measure the effect of the direct oral anticoagulants (DOACs) are not available. This study evaluates a point-of-care (PoC) coagulometer to assess the anticoagulant effects of the DOACs and low molecular weight heparin. Studies were done in fresh spiked blood from healthy volunteers. PoC coagulometer baseline clotting times were half that of the manual whole blood clotting time (WBCT, legacy method) and exhibited a sensitivity to DOAC anticoagulation approximately twice that of WBCT. All %CV values for both methods were < 10% with most being < 5% indicating acceptable precision of both methods. R2 values for both clotting time and percent rise from baseline were > 0.98 indicating a strong correlation between the two methods. Replicate measurements for all subjects showed a maximum upper %CV value of 5.56% and a maximum upper value of all absolute %Differences of 5.5%, with both criteria meeting predefined acceptance criteria. The dose-response curves for all subjects were linear across the concentration ranges tested. The Perosphere Technology PoC coagulometer detects a range of therapeutic levels of the DOACs apixaban, rivaroxaban, edoxaban, and dabigatran, as well as the low molecular weight heparin, enoxaparin, with high precision and sensitivity. Please check and confirm the processed affiliations are correct . and amend if necessary.

Anticoagulation reversal (vitamin K, prothrombin complex concentrates, idarucizumab, andexanet-α, protamine)

Bleeding events are common in patients prescribed anticoagulants and can have devastating consequences. Several specific and nonspecific agents have been developed to reverse the effects of anticoagulant drugs or toxins. Vitamin K, as the oldest of these antidotes, specifically counteracts the effects of pharmaceuticals and rodenticides designed to deplete stores of vitamin K-dependent factors. In cases of life-threatening bleeding, the addition of prothrombin complex concentrates (PCCs) allows for the immediate replacement of coagulation factors. While the use of PCCs has been extended to the non-specific reversal of the effects of newer direct oral anticoagulants, the specific agents idarucizumab, targeting dabigatran and andexanet-α, binding factor Xa inhibitors, have recently been developed and are being preferentially recommended by most guidelines. However, despite having rapid effects on correcting coagulopathy, there is to date a lack of robust evidence establishing the clear superiority of direct oral anticoagulant-specific reversal agents over PCCs in terms of haemostatic efficacy, safety or mortality. For andexanet-α, a potential signal of increased thromboembolic risks, comparatively high costs and low availability might also limit its use, even though emerging evidence appears to bolster its role in intracranial haemorrhage. Protamine is the specific agent for the reversal of unfractionated heparin anticoagulation used mainly in cardiovascular surgery. It is much less effective for low molecular weight heparin fragments and is usually reserved for cases with life-threatening bleeding.

Stroke severity and outcomes in patients with intracerebral hemorrhage on anticoagulants and antiplatelet agents: An analysis from the Japan Stroke Data Bank

BACKGROUND AND AIM

Some patients with intracerebral hemorrhage are on antithrombotic agents at the time of the event and these may worsen outcome, but the relative risk of different oral anticoagulants and antiplatelet agents is uncertain. We determined associations between pre-onset intake of antithrombotic agents and initial stroke severity, and outcomes, in patients with intracerebral hemorrhage.

METHODS

Patients with intracerebral hemorrhage admitted within 24 h after onset between January 2017 and December 2020 and recruited to the Japan Stroke Data Bank, a hospital-based multicenter prospective registry, were included. Enrolled patients were classified into four groups based on the type of antithrombotic agents being used on admission. The outcomes were the National Institutes of Health Stroke Scale (NIHSS) score on admission and modified Rankin Scale (mRS) of 5-6 at discharge.

RESULTS

Of a total 9810 patients with intracerebral hemorrhage (4267 females; mean age = 70 ± 15 years), 77.1% were classified into the no-antithrombotic group, 13.2% into the antiplatelet group, 4.0% into the warfarin group, and 5.8% into the direct oral anticoagulant (DOAC) group. Median (interquartile range) NIHSS score on admission was 12 (5-22), 13 (5-26), 15 (5-30), and 13 (6-24), respectively, in the four groups. In multivariable analysis, the prestroke warfarin use was associated with higher NIHSS score (adjusted incidence rate ratio = 1.09 (95% confidence interval (CI) = 1.06-1.13), with the no-antithrombotic group as the reference), but the antiplatelet group (1.00 (95% CI = 0.98-1.02)) and DOAC group (0.98 (95% CI = 0.95-1.01)) were not. The rate of mRS 5-6 at discharge was 30.8%, 41.9%, 48.6%, and 41.5%, respectively, in the four groups. In multivariable analysis, prestroke warfarin use was associated with mRS 5-6 (adjusted odds ratio = 1.90 (95% CI = 1.28-2.81), with the no-antithrombotic group as the reference), but the antiplatelet group (1.12 (95% CI = 0.91-1.37)) and DOAC group (1.25 (95% CI = 0.88-1.77)) were not.

CONCLUSION

Patients who were taking warfarin prior to intracerebral hemorrhage onset suffered more severe intracerebral hemorrhage as evidenced by higher admission NIHSS and higher discharge mRS. In contrast, no increase in severity was seen with antiplatelet agents.

A Clinical Practice-Based Comparison of Conventional and Individualized Dosing Strategies for Therapeutic Enoxaparin

To understand differences in anti-factor-Xa levels produced by two different dosing strategies (conventional and individualized) for therapeutic enoxaparin in a cohort of hospital inpatients. A multicenter, retrospective cohort study over a two- and a half-year period for inpatients with stable renal function and on therapeutic enoxaparin. Anti-factor-Xa levels were taken 3-5 h after enoxaparin administration and a minimum of 48 h of dosing. The final analysis included 278 patients from five hospitals: conventional dosing was used for 141, while 137 were given an unconventional dose, that is, individualized for their renal function and weight. Out-of-range levels were frequent (35% to 40% of all inpatients). After adjustment for age, renal function, and body mass index (BMI), the conventional group was more likely to experience above-range levels (> 1.0 IU/mL; OR 2.50 [95% CI 1.38-4.56], p < 0.003) than the individualized group. Individualized dosing was independently associated with higher odds of a below-range anti-Xa level (< 0.5 IU/mL) compared to conventional dosing (OR 2.27 [95% CI 1.07-4.76], p = 0.03). Within the conventional group, above-range levels were significantly and independently associated with decreasing renal function (OR 0.97, 95% CI 0.96-0.99, p = 0.004) and with increasing BMI (OR 1.06, 95% CI 1.01-1.10, p = 0.02). No such associations were seen with an individualized approach. Clinical event rates were low and not different between groups (p > 0.24). Conventional therapeutic dosing of enoxaparin exposed people with obesity or renal impairment to more frequent above-range anti-factor-Xa levels; individualizing the dose could improve this but might expose people to subtherapeutic levels. More research is needed.

The impact of anticoagulant-related bleeding on quality of life: Development of a novel measure based on perspectives from older adults

BACKGROUND

Venous thromboembolism (VTE) and atrial fibrillation (AF) disproportionately affect older adults, who are at increased risk of bleeding from treatment with anticoagulant therapy. The impact of bleeding on older adults' quality of life (QoL) is poorly understood due to the lack of a validated measure of their experience. This study's purpose is to describe the first evidence-based steps in developing a new condition-specific patient-reported outcome measure (PROM) for the effect of anticoagulant-related bleeding on older adults' QoL.

METHODS

Adults aged 65 years and older with VTE or AF at the University of Utah who were eligible for anticoagulation were recruited. We purposely sampled by age, sex, race/ethnicity, diagnosis, bleeding history and anticoagulant. In accordance with evidence-based guidelines for PROM development, focus groups were conducted to refine a hypothesized conceptual model of bleeding-related QoL and analyzed according to hybrid inductive and deductive thematic analysis methods. Focus group results were used to write a draft PROM. Semi-structured qualitative interviews were conducted to revise items on the draft PROM and were analyzed using thematic analysis to generate a final bleeding-related QoL PROM.

RESULTS

Twenty individuals participated in interviews, and nine in two focus groups. Median age was 81 (range 69-95), 52% were women and 69% were White (10% Asian, 10% Hispanic, 7% Black, 3% Native Hawaiian/Pacific Islander). Through inductive and deductive thematic analysis of focus groups, we identified 19 themes (e.g., specific bleeding symptoms, adaptations in relationships, fatigue) that fell into 5 domains: 1) bleeding symptoms, 2) healthcare experiences, 3) social function, 4) emotional function, 5) physical function. These 19 themes and 5 domains formed the basis of the draft PROM. We conducted semi-structured cognitive interviews, and we performed thematic analysis to revise the drafted measure for clarity and relevance. The data resulted in a new PROM for bleeding-related QoL in older adults.

CONCLUSION

Employing evidence-based methods for PROM development, we found that bleeding can have a marked impact on everyday activities, emotional wellbeing and interpersonal relations for older adults. We incorporated these distinct aspects of wellbeing and function into a novel PROM for bleeding-related QoL that can inform clinical care and research after subsequent psychometric validation.

Recto Sigmoid Sub-Mucosal Bleeding Due to Warfarin over Anticoagulation Presenting as Intestinal Obstruction

Patients on anticoagulation therapy, particularly those on warfarin, are at risk of gastrointestinal bleeding, gum bleeding, hematuria, and ecchymosis. However, it is rare for such patients to present with intramural or submucosal bleeding leading to intestinal obstructive symptoms. Sub-mucosal intestinal bleeding due to prolonged anticoagulant use is uncommon. Literature suggests that the duodenum and small intestine are common locations for anticoagulant-induced hematomas, occurring in approximately 1 case per 2,500 anticoagulated patients per year. However, intramural colonic hematomas are rarely reported. Spontaneous anticoagulant induced hematomas may develop as early as 10 days after starting therapy. We report the case of a 63-year-old female who presented with recto-sigmoid sub-mucosal bleeding causing obstructive symptoms. The patient was managed surgically with laparotomy, resulting in significant improvement, and was scheduled for follow-up to evaluate the feasibility of reintroducing anticoagulation therapy.

Atrial fibrillation management in older hospitalized patients: Evidence of a poor oral anticoagulants prescriptive attitude from the Italian REPOSI registry

Atrial fibrillation (AF) prevalence increases in older patients which also show a high thromboembolic risk. Oral anticoagulants (OACs) are recommended to prevent cardioembolic events and direct oral anticoagulants (DOACs) improved anti-thrombotic treatment. However, the benefits/risks of anticoagulant in older patients still need to be completely defined. This retrospective observational study aimed to describe the treatment with OACs in older AF hospitalized patients, and to identify factors influencing OAC therapy or discontinuation using the REgistro Politerapie SIMI. Univariate and multivariate logistic regression models were applied to identify predictors of OACs treatment and discontinuation. Cox proportional hazards models were performed to evaluate one-year mortality by treatment groups. AF patients were 1,128(26.5 %) at discharge and 1,098(97.3 %) required OAC treatment; about half of them (N = 528;48.1 %) were no-OACs users; 236(21.5 %) and 334(30.4 %) used DOACs and VKA, respectively. Increasing DOACs use was observed during the study period. Predictors of OACs treatment were: BMI (OR:1.04; 95 %CI:1.01-1.07), Barthel index (OR:1.01; 95 %CI:1.01-1.02), medications number (OR:1.07; 95 %CI:1.01-1.13). Conversely, a lower probability was found in patients with a high CIR.S (OR:0.59; 95 %CI:0.36-0.97) and neoplasm (OR:0.57; 95 %CI:0.37-0.88). Hospital stay (OR:1.02; 95 %CI:1.01-1.05), neoplasm (OR:2.25; 95 %CI:1.07-4.70) and INR (OR:1.21; 95 %CI:1.05-1.40) increased OACs discontinuation. A lower discontinuation was observed in dyslipidemic patients (OR:0.18; 95 %CI:0.04-0.82) and heart failure (OR:0.38; 95 %CI:0.21-0.70). Among AF patients, 157(14.3 %) died during the follow-up year. Age (HR = 1.05; 95 %CI = 1.03-1.08) and CIR.S (HR = 2.54; 95 %CI = 1.53-4.21) were associated with a greater mortality risk. In conclusion, critical issues related to the underuse and discontinuation of OACs therapy in hospitalized older patients were highlighted.

Long-Term Safety of a Four-Factor Prothrombin Complex Concentrate (Kcentra®/Beriplex® P/N): An Updated Pharmacovigilance Review

INTRODUCTION

 Four-factor prothrombin complex concentrate (4F-PCC) is recommended for vitamin K antagonist reversal in patients with major bleeding or in need of surgery. The most important risk associated with the use of 4F-PCC is the occurrence of thromboembolic events (TEEs). In this review, we aim to evaluate the safety profile of a 4F-PCC (Kcentra®/Beriplex® P/N; CSL Behring, Marburg, Germany) by reviewing pharmacovigilance data.

METHODS

 A retrospective analysis of postmarketing pharmacovigilance data of Kcentra®/Beriplex® P/N from February 1996 to April 2022 was performed and complemented by a review of clinical studies published between January 2012 and April 2022.

RESULTS

 A total of 2,321,443 standard infusions of Kcentra®/Beriplex® P/N were administered during the evaluation period. Adverse drug reactions (ADRs) were reported in 614 cases (∼1 per 3,781 standard infusions) and 233 of these cases (37.9%) experienced suspected TEEs related to 4F-PCC (∼1 per 9,963 standard infusions); most of these cases had pre-existing or concomitant conditions likely to be significant risk factors for thrombosis. TEE rates were similar when 4F-PCC was used on-label or off-label for direct oral anticoagulant-associated bleeding. Thirty-six cases (5.9%) reported hypersensitivity type reactions (∼1 per 64,485 standard infusions). No confirmed case of viral transmission related to 4F-PCC use was reported. The published literature also revealed a favorable safety profile of 4F-PCC.

CONCLUSION

 Analysis of postmarketing pharmacovigilance safety reports demonstrated that treatment with 4F-PCC was associated with few ADRs and a low rate of TEEs across multiple indications and settings, thus confirming a positive safety profile of 4F-PCC.

Finding individualised treatment in obese needing enoxaparin (FIT ONE): a multicentre study of therapeutic enoxaparin and the role of anti-factor Xa monitoring

Enoxaparin is dosed according to actual body weight in treatment of arterial and venous thrombosis. Due to its hydrophilic nature, it distributes according to lean body mass which may be problematic when dosing obese patients as this may increase the risk of bleeding events in this population. The aim was to evaluate current therapeutic enoxaparin dosing strategies, including Antifactor Xa (AFXa) level monitoring, in obese patients and to identify factors that contribute to treatment failure and excess anticoagulation. A retrospective cohort study was conducted reviewing patients administered therapeutic enoxaparin between May 2020 and April 2021. Data were collected on patient characteristics, enoxaparin therapy, AFXa monitoring, and outcomes. Regression models were constructed to assess variables of interest to estimate any association with AFXa levels. In total 762 patients were included in the analysis. The mean initial weight-based dose was 0.95 mg/kg twice daily (SD: ± 0.12, IQR 0.92-1.01) and 1.04 mg/kg once daily (SD: ± 0.26, IQR 0.93-1.12) and 14.4% of patients had AFXa monitoring. Treatment failure was experienced by 2.2%, 5% experienced bleeding. There was no association between the mean actual milligram per kilogram weight-based twice daily doses and subtherapeutic, therapeutic and supratherapeutic AFXa levels (P = 0.135). Obesity was not included in the final regression models due to lack of significance. At a mean therapeutic enoxaparin dose of 0.95 mg/kg twice daily and 1.04 mg/kg once daily no excess in treatment failure or bleeding events were observed in obese patients compared to the product information. Obesity was not an independent variable that affected the achievement of target AFXa levels.

Consensus Based Indian Guidelines for the Management of Pemphigus Vulgaris and Pemphigus Foliaceous

Pemphigus is an autoimmune blistering disorder characterized by the presence of intraepidermal blisters and erosions, primarily affecting the mucosa and/or skin. There are no established Indian guidelines for the management of pemphigus, and Western guidelines cannot be directly applied due to differences in clinicodemographic profiles, comorbidities, and resource limitations. These guidelines aim to provide Indian dermatologists with evidence-based and consensus-driven recommendations for the management of pemphigus vulgaris (PV) and pemphigus foliaceous (PF), taking into account the unique challenges posed by the Indian healthcare setting. The guidelines focus on the comprehensive management of PV and PF, addressing diagnosis, treatment, monitoring, and follow-up. It is intended for dermatologists working in both outpatient and inpatient settings across India. The first draft of the guidelines was prepared by the writing group and then reviewed by 19 national experts in pemphigus management, including inputs from allied specialties. Areas with limited evidence or anticipated variation in recommendations were subjected to rounds of voting, with responses categorized as "strongly agree," "agree," "neutral," "disagree," or "strongly disagree." Suggestions were incorporated, and statements were revised until a mean agreement score of 4 or higher was reached across 16 key areas after four voting rounds. These guidelines offer a structured approach to managing pemphigus in India, addressing the need for region-specific recommendations that account for unique challenges such as resource constraints and specific comorbidities in Indian patients. They serve as a valuable resource for dermatologists treating pemphigus in a range of clinical settings.

Atrial Fibrillation and Cancer-Epidemiology, Mechanisms, and Management

Atrial fibrillation (AF) and cancer are increasingly recognized as interrelated conditions, with cancer patients showing elevated incidences of AF, and there is evidence that AF may sometimes precede cancer diagnoses. This comprehensive review investigates the epidemiology, pathophysiology, and management challenges associated with AF in cancer patients. Epidemiologically, several cancers are more closely related to increased rates of AF, including lung, colorectal, gastrointestinal, and hematologic malignancies. Mechanistically, both AF and cancer share pathophysiological pathways centered on inflammation, oxidative stress, and common cardiovascular risk factors, such as hypertension, obesity, and diabetes. The inflammatory microenvironment in tumors, marked by increased cytokines and growth factors, promotes atrial remodeling and AF susceptibility. Elevated reactive oxygen species (ROS) levels, driven by the metabolic demands of cancer, further contribute to atrial fibrosis and structural changes. Moreover, many anticancer treatments exacerbate AF risk. Management of AF in cancer patients presents many unique challenges and requires a multidisciplinary approach. Rate and rhythm control strategies are complicated by potential drug-drug interactions and limited data surrounding early implementation of rhythm control strategies in cancer patients. Interventional approaches such as catheter ablation, though effective in maintaining sinus rhythm, carry significant perioperative risk in patients with malignancy. Stroke prevention with anticoagulants is essential but requires cautious administration to avoid heightened bleeding risks, particularly in patients undergoing chemotherapy. Further, the limited applicability of standard risk stratification tools like CHA2DS2-VASc in this population complicate decisions regarding anticoagulation. This review highlights the bidirectional relationship between AF and cancer, the difficulties in management, and the critical need for further research in this field.

Anticoagulation approach in morbid obesity: a comprehensive review on venous thromboembolism management

Obesity is a recognized risk factor for venous thromboembolism (VTE), associated with distinct challenges in managing anticoagulation therapy. There is still limited evidence regarding the impact of extreme body weight on the pharmacokinetics, pharmacodynamics, efficacy, and safety of various anticoagulant medications. To our knowledge, this is the first comprehensive review to address both prophylactic and therapeutic anticoagulant dosages specifically for managing VTE in patients with a body mass index (BMI) ≥40 kg/m2 or weight ≥120 kg. Our aim was to synthesize the findings of relevant studies alongside the latest recommendations on anticoagulation in this unique population. We gathered and analyzed data on all classes of anticoagulants available for VTE management, including vitamin K antagonists (VKAs), unfractionated heparin (UFH), low-molecular-weight heparin (LMWH), fondaparinux, and direct oral anticoagulants (DOACs), offering insights into their efficacy and safety profiles. Additionally, we explored special subpopulations of morbidly obese patients, such as those with cancer, renal dysfunction, or those undergoing bariatric surgery, recognizing the nuanced therapeutic challenges they present. The current evidence for anticoagulant therapy in morbidly obese patients with VTE is evidently insufficient, underscoring the need for a tailored approach and meticulous monitoring to achieve an optimal therapeutic balance.

Multidisciplinary Expert Guidance for the Management of Severe Bleeding on Oral Anticoagulation: An Algorithm for Practicing Clinicians

Bleeding complications associated with oral anticoagulant (OAC) frequently lead to emergency department visits and hospitalization. Short-term all-cause mortality after severe bleeding is substantial ranging from approximately 10% for gastrointestinal bleeding (the most frequent single site) to approximately 50% for intracranial bleeding. A protocol for multidisciplinary approach to bleeding is needed to (i) ensure rapid identification of patients at risk of adverse outcomes, (ii) optimize delivery of supportive measures, (iii) treat the source of bleeding, and (iv) administer anticoagulant reversal or hemostatic therapies judiciously for patients most likely to benefit. We convened a multidisciplinary panel of experts (emergency medicine, gastroenterology, general internal medicine, hematology, neurology, pharmacy, thrombosis) to review the literature and provide practical guidance including a corresponding algorithm for use at the point of care to assist clinicians in the management of patients with acute severe OAC-related bleeding.

Gender-affirming hormone therapy in the transgender patient: influence on thrombotic risk

Research regarding the hematologic sequelae of estrogen and testosterone therapy for transgender people is an emerging area. While estrogen therapy has been widely studied in cisgender women, studies in transgender individuals are limited, revealing variable adverse effects influenced by the dose and formulation of estrogen used. Thrombotic risk factors in transgender and gender-diverse individuals are multifactorial, involving both modifiable and nonmodifiable factors. Management of venous thromboembolism (VTE) in individuals receiving gender-affirming estrogen entails standard anticoagulation therapy alongside shared decision-making regarding hormone continuation and risk factor modification. While data and guidance from cisgender women can offer a reference for managing thrombotic risk in transgender individuals on hormone therapy, fully applying these insights can be challenging. The benefits of gender-affirming hormone therapy include significantly reducing the risk of suicide and depression, highlighting the importance of a contemplative approach to the management of hormonal therapy after a VTE event. Although limited, the available data in the literature indicate a low thrombotic risk for transgender individuals undergoing gender-affirming testosterone therapy. However, polycythemia is a common adverse effect necessitating monitoring and, occasionally, adjustments to hormonal therapy. Additionally, iron deficiency may arise due to the physiological effects of testosterone or health care providers' use of phlebotomy, an aspect that remains unstudied in this population. In conclusion, while the set of clinical data is expanding, further research remains vital to refine management strategies and improve hematologic outcomes for transgender individuals undergoing gender-affirming hormone therapy.

Warfarin and heparin monitoring in antiphospholipid syndrome

Anticoagulation is central to the management of antiphospholipid syndrome (APS), an acquired thrombo-inflammatory disorder characterized by thrombosis (venous, arterial, or microvascular) or pregnancy morbidity, in association with persistent antiphospholipid antibodies (aPL; ie, 1 or more of lupus anticoagulant [LA], anticardiolipin, anti-beta-2- glycoprotein I, IgG, or IgM antibodies). The mainstay of anticoagulation in patients with thrombotic APS is warfarin or an alternative vitamin K antagonist (VKA) and, in certain situations, low-molecular-weight heparin (LMWH) or unfractionated heparin (UFH). Accurate assessment of anticoagulation intensity underpins optimal anticoagulant dosing for thrombus treatment or primary/secondary prevention. In patients with APS on warfarin, the international normalized ratio (INR) may not be representative of anticoagulation intensity due to an interaction between LA and the thromboplastin reagent used in the INR determination. In this review, we summarize the use of warfarin/VKA in patients with APS, along with venous and point-of-care INR monitoring. We also discuss the role and monitoring of LMWH/UFH, including in the anticoagulant refractory setting and during pregnancy.

Anticoagulation at the end of life: whether, when, and how to treat

Nearly 2 out of 3 patients with venous thromboembolism (VTE) and 1 out of 4 patients with atrial fibrillation (AF) will die within the year. Whether, when, and how to manage anticoagulation at the end of life requires many trade-offs. Patients and clinicians must balance symptom burden, greatly elevated bleeding and thrombosis risks, competing comorbidities and medications, and changing goals over time. This review uses cases of VTE and AF to present a framework for care that draws upon existing disease-specific data and cutting-edge palliative care science. It reviews strategies for the difficult task of estimating a patient's prognosis, characterizes the enormous public health burden of anticoagulation in serious illness, and analyzes the data on anticoagulation outcomes among those with limited life expectancy. Finally, an approach to individualized decision-making that is predicated on patients' priorities and evidence-based strategies for starting, continuing, or stopping anticoagulation at the end of life are presented.

Early Thrombus Removal for Acute Lower Extremity Deep Vein Thrombosis: Update on Inclusion, Technical Aspects, and Postprocedural Management

Acute lower extremity deep vein thrombosis (DVT) is a common disorder with significant associated morbidity, including pain and swelling, as well as the risk of pulmonary embolism (PE), recurrent venous thromboembolism (VTE) and chronic debilitating post-thrombotic syndrome (PTS). Anticoagulation is standard of care for DVT treatment. It assists in reducing thrombus progression and the occurrence of PE, but incomplete DVT resolution increases the risk of recurrent VTE, valvular insufficiency, and PTS. Endovascular DVT interventions, such as catheter-directed thrombolysis, pharmacomechanical thrombectomy, and large-bore mechanical thrombectomy offer an alternative therapeutic strategy for DVT management. This paper will discuss technical factors and current issues when performing lower extremity DVT interventions including patient selection, anticoagulation, choice of device for endovascular thrombus removal, adjunctive techniques, and venous stent management.Level of Evidence: No level of evidence for: review articles, basic science, laboratory investigations, and experimental study articles.

Rate of recurrence after discontinuing anticoagulation in patients with venous thromboembolism within 30 days after COVID-19 vaccine

This study generated evidence to guide anticoagulation in patients with VTE after vaccination for COVID-19. We provided data on the low recurrence rate after cessation of anticoagulant therapy and the findings for this study offer timely insights into the management of a potentially vaccine-related adverse event.

Comparing tele-pharmacy and standard clinic follow-up for newly initiated warfarin anticoagulation therapy: A retrospective study

OBJECTIVES

To compare the effectiveness of providing telepharmacy anticoagulation to on-site clinics in achieving optimal outcomes for patients newly starting warfarin.

METHODS

This single-center retrospective cohort study included adult patients who started warfarin for the first time and were monitored by clinical pharmacists either on-site or via telepharmacy anticoagulation clinics between January 2017 and March 2024. The primary outcome is to compare the time in therapeutic range (TTR) between the 2 groups. The secondary outcome is the occurrence of anticoagulation therapy-related complications.

RESULTS

We included 191 patients, with 77 in the telepharmacy group and 114 in the on-site group. The baseline characteristics were similar for both groups. The primary outcome- time in therapeutic range (TTR)-was not significantly different between thetelepharmacy and the on-site groups (50% versus 53.8%, p=0.455) and remained so after univariable and multivariable adjustments (OR [odd ratio]= 0.63, p=0.14 and OR=0.58, p=0.102). Additionally, there were no significant differences in secondary outcomes, including thromboembolism and bleeding (p=1 for both).

CONCLUSION

This study demonstrates that patients who receive warfarin for the first time at an anticoagulation clinic can use the telepharmacy method without the fear undesirable outcomes. Results of this study support the continued use and expansion of telepharmacy services in Saudi Arabia. However, further research larger sample sizes and multiple centers is needed to confirm these findings.

Changes in the landscape of anticoagulation: a focus on direct oral anticoagulants

Over the last decade, the advent of direct oral anticoagulants (DOACs) has rapidly changed the landscape of anticoagulation. In the early 2010s, DOACs became widely available for stroke prevention in atrial fibrillation and the treatment of venous thromboembolism. About 10 years later, approximately two-thirds of patients requiring oral anticoagulant treatment were receiving a DOAC. The results of several post-marketing studies consistently confirmed the findings of phase 3 clinical trials, and research has focused on new areas of development, with heterogeneous results. A role for DOACs has emerged for patients with peripheral artery disease and other challenging conditions, such as cancer-associated thrombosis, unusual-site venous thromboembolism, and end-stage renal disease. Conversely, clinical trials showed that DOACs were not efficacious in patients with valvular atrial fibrillation, mechanical heart valves, embolic strokes of undetermined source, or antiphospholipid syndrome. In this Review, we discuss the impact of DOACs in clinical practice over the last decade, new areas under development, and practical issues in the management of these drugs.

Determination of the optimal obesity-adjusted dosing weight for enoxaparin

AIMS

The ideal dosing weight metric for enoxaparin remains elusive. Dosing remains focused on actual body weight, which may inadvertently increase the risk of bleeding in those with obesity, or ideal weight, which may underdose those with obesity. Our aim was to determine the optimal obesity-adjusted enoxaparin dosing weight.

METHODS

Multisite retrospective data were collected over a 2.0-year period for those with minimum 48 h of in-hospital twice-daily enoxaparin and factor anti-Xa level 3-5 h postdose (n = 220). Multiple linear regression calculated the associated variance between a range of nominal dosing weights and factor anti-Xa levels, adjusted for renal function. Dosing weights were calculated as ideal body weight (IBW) and then adjusted for increasing percentages of weight above IBW, i.e. IBW + 10% above IBW, IBW + 20% etc. up to actual body weight. A similar approach was used for lean body weight (LBW).

RESULTS

For body mass index ≥30 kg/m2 optimal variance explained by dosing weight metrics was at IBW + 40% (23%) and similarly for LBW + 40% (23%). Using actual body weight (ABW) had lowest associated variance with factor anti-Xa levels (18%) followed by unadjusted IBW (13%) or unadjusted LBW (19%). In those with body mass index <30 kg/m2 there was similar associated variance in the ranges of IBW + 20-50% and LBW 10-40% (21%).

CONCLUSION

Compared to IBW + 40% or LBW + 40% use of ABW to calculate dose was poorly associated with factor anti-Xa levels, as was IBW or LBW. IBW + 40% and LBW + 40% require further study as a dosing weight metric and may provide a more consistent factor anti-Xa response in those with obesity.

Urgent Reversal of Direct Oral Anticoagulants in Critical and Life-Threatening Bleeding: A Multidisciplinary Expert Consensus

Direct oral anticoagulants (DOACs) are increasingly being used due to their improved efficacy/safety ratio and lower clinical and economic burden when compared to vitamin K antagonists. However, bleeding is still the most frequent complication associated with DOACs, and although rare, bleeding episodes can be life-threatening or critical. The impact of DOAC anticoagulation activity during a bleeding event must be evaluated according to patient clinical assessment, dosage and time from last intake, the presence of comorbidities (especially kidney and liver dysfunction), and, whenever possible, coagulation tests. Unfortunately, DOACs' anticoagulation activity is not easily or usually detectable in routine common coagulation testing. Specific DOAC tests allow for specific drug monitoring, but they are too time consuming, and are usually unavailable in routine emergency practice. If a clinically relevant DOAC plasma concentration is assumed or proven in a severe bleeding scenario, DOAC reversal is needed to restore hemostasis. This experts' consensus provides a narrative review about DOAC reversal and practical life-threatening bleeding management in several scenarios (trauma, intracranial hemorrhage and gastrointestinal bleeding), focusing on the selection of patients to whom specific reversal agents should be given.

Update on antithrombotic therapy and body mass: a clinical consensus statement of the European Society of Cardiology Working Group on Cardiovascular Pharmacotherapy and the European Society of Cardiology Working Group on Thrombosis

Obesity and underweight are a growing health problem worldwide and a challenge for clinicians concerning antithrombotic therapy, due to the associated risks of thrombosis and/or bleeding. This clinical consensus statement updates a previous one published in 2018, by reviewing the most recent evidence on antithrombotic drugs based on body size categories according to the World Health Organization classification. The document focuses mostly on individuals at the extremes of body weight, i.e. underweight and moderate-to-morbid obesity, who require antithrombotic drugs, according to current guidelines, for the treatment or prevention of cardiovascular diseases or venous thromboembolism. Managing antithrombotic therapy or thromboprophylaxis in these individuals is challenging, due to profound changes in body composition, metabolism and organ function, and altered drug pharmacokinetics and pharmacodynamics, as well as weak or no evidence from clinical trials. The document also includes artificial intelligence simulations derived from in silico pharmacokinetic/pharmacodynamic models, which can mimic the pharmacokinetic changes and help identify optimal regimens of antithrombotic drugs for severely underweight or severely obese individuals. Further, bariatric surgery in morbidly obese subjects is frequently performed worldwide. Bariatric surgery causes specific and additional changes in metabolism and gastrointestinal anatomy, depending on the type of the procedure, which can also impact the pharmacokinetics of antithrombotic drugs and their management. Based on existing literature, the document provides consensus statements on optimizing antithrombotic drug management for underweight and all classes of obese patients, while highlighting the current gaps in knowledge in these complex clinical settings, which require personalized medicine and precision pharmacology.

Incidence, Predictors, and Outcomes of Venous and Arterial Thrombosis in COVID-19: A Nationwide Inpatient Analysis

BACKGROUND

Coronavirus disease 2019 (COVID-19) is known to increase the risk of venous thromboembolism (VTE) and arterial thromboembolism (ATE). However, the incidence, predictors, and outcomes of clinical thrombosis for inpatients with COVID-19 are not well known. This study aimed to enhance our understanding of clinical thrombosis in COVID-19, its associated factors, and mortality outcomes.

METHOD

Hospitalised adult (≥18 years of age) patients with COVID-19 in 2020 were retrospectively identified from the US National Inpatient Sample database. Clinical characteristics, incident VTE, ATE, and in-hospital mortality outcomes were recorded. Multivariable logistic regression was performed to identify clinical factors associated with thrombosis and in-hospital mortality in COVID-19 inpatients.

RESULTS

A total of 1,583,135 adult patients with COVID-19 in the year 2020 were identified from the National Inpatient Sample database; patients with thrombosis were 41% females with a mean age of 65.4 (65.1-65.6) years. The incidence of thrombosis was 6.1% (97,185), including VTE at 4.8% (76,125), ATE at 3.0% (47,790), and the in-hospital mortality rate was 13.4% (212,785). Patients with thrombosis were more likely to have respiratory symptoms of COVID-19 (76.7% vs 75%, p<0.001) compared with patients without thrombosis. The main factors associated with overall thrombosis, VTE, and ATE were paralysis, ventilation, solid tumours without metastasis, metastatic cancer, and acute liver failure. Although all thrombosis categories were associated with higher in-hospital mortality for COVID-19 inpatients in univariable analyses (p<0.001), they were not in multivariable analyses-thrombosis (odds ratio [OR] 1.24; 95% confidence interval [CI] 0.90-1.70; p=0.19), VTE (OR 0.70; 95% CI 0.52-1.00; p=0.05), and ATE (OR 1.07; 95% CI 0.92-1.25; p=0.36).

CONCLUSIONS

The association of COVID-19 with thrombosis and VTE increases with increasing severity of the COVID-19 disease. Risk stratification of thrombosis is crucial in COVID-19 patients to determine the necessity of thromboprophylaxis.

Rate and predictors of thromboprophylaxis in internal medicine wards: Results from the AURELIO study

BACKGROUND

Randomized controlled trials suggest that prophylactic doses of anticoagulants effectively prevent venous thromboembolism (VTE) in hospitalized medical patients with high thromboembolic risk. However, no prospective studies exist regarding the real-world prevalence of prophylactic anticoagulant use. This prospective study aimed to determine the rate and predictors of thromboprophylaxis in an unselected population of patients hospitalized in medical departments.

METHODS

We conducted a multicenter prospective observational study (AURELIO - rAte of venous thrombosis in acutely iLl patIents hOspitalized) to assess the rate of deep vein thrombosis (DVT) in unselected acutely ill patients hospitalized in medical wards using compression ultrasound (CUS) at admission and discharge. Additionally, we evaluated the rate of pharmacological thromboprophylaxis administration in this population and analyzed the thrombotic risk by assessing RAMs (Risk Assessment Models) such as the IMPROVE-VTE and PADUA scores following the clinician's decision to administer thromboprophylaxis. Patients with IMPROVE-VTE scores ≥3 and/or PADUA scores ≥4 were classified as high thrombotic risk; those with IMPROVE-VTE scores <3 and/or PADUA scores <4 were classified as low risk.

RESULTS

We recruited 2371 patients (1233 males [52 %] and 1138 females [48 %]; mean age 72 ± 16 years). The median length of hospitalization was 13 ± 12 days. Overall, 442/2371 (18.6 %) patients received prophylactic parenteral anticoagulants (subcutaneous low weight molecular heparin or fondaparinux once daily) at admission. Assessing the thrombotic risk of the population recruited 1016 (42.9 %) patients were classified as high risk and 1354 (57.1 %) were low risk. Among high-risk patients, 339/1016 (33.4 %) received anticoagulant prophylaxis compared to 103/1354 (7.6 %) low-risk patients. During hospitalization, 9 patients developed DVT, comprising 7 asymptomatic and 2 symptomatic cases of proximal DVT. Of these, 3 patients were on anticoagulant prophylaxis, while 6 were not. Among the high-risk population, 7 out of 1016 patients (0.7 %) experienced proximal DVT during hospitalization, with 2 out of these 7 (28 %) receiving anticoagulant thromboprophylaxis. In the low-risk population, 2 out of 1354 patients (0.2 %) developed DVT, with 1 out of these 2 (50 %) receiving anticoagulant thromboprophylaxis. Age, heart or respiratory failure, pneumonia, active neoplasia, previous VTE, reduced mobility, and absence of kidney failure were more frequent in patients receiving prophylaxis. Multivariable logistic regression identified age (RR 1.010; CI 95 % 1002-1019; p = 0.015), heart/respiratory failure (RR 1.609; CI 95 % 1248-2075; p < 0.0001), active neoplasia (RR 2.041; CI 95 % 1222-2141; p < 0.0001), pneumonia (RR 1.618; CI 95 % 1557-2676; p < 0.0001), previous VTE (RR 1.954; CI 95 % 1222-3125; p < 0.0001), and reduced mobility (RR 4.674; CI 95 % 3700-5905; p < 0.0001) as independent predictors of thromboprophylaxis.

CONCLUSIONS

This study, conducted without pre-established thromboembolic risk scores, offers a comprehensive view of venous thromboembolism prophylaxis in medical patients with acute conditions hospitalized in internal medicine departments. It reveals that advanced age, heart or respiratory failure, active cancer, pneumonia, previous VTE, and reduced mobility are predictors that may influence the decision to administer thromboprophylaxis in these patients.

Efficacy and Safety of Andexanet Alfa Versus Four Factor Prothrombin Complex Concentrate for Emergent Reversal of Factor Xa Inhibitor Associated Intracranial Hemorrhage: A Systematic Review and Meta-Analysis

Factor Xa inhibitors (FXaI) are increasingly used for anticoagulation therapy, yet their association with intracranial hemorrhage poses a significant challenge. Although andexanet alfa (AA) and four-factor prothrombin complex concentrate (4F-PCC) have shown promise in reversing FXaI effects, their comparative efficacy and safety remain uncertain. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we conducted a literature search on electronic databases to obtain the relevant studies until May 16, 2024. Our primary outcomes were successful anticoagulation reversal, overall mortality (including 30-day and in-hospital mortality), and thromboembolic events. Secondary outcomes were length of hospital and intensive care unit stay and hematoma volume expansion. Data were pooled using a random-effects model. We included 16 eligible studies with a total of 2,977 patients. A statistically significant improvement in hemostatic efficacy rates was in favor of the AA group (risk ratio [RR] 1.10, 95% confidence interval [CI] 1.01-1.20, P = 0.02). Lower overall mortality rates were found in the AA group (RR 0.67, 95% CI 0.51-0.88, P = 0.004). However, no difference was found in 30-day mortality rates (RR 0.82, 95% CI 0.58-1.16, P = 0.26). In terms of thromboembolic events, more events were found in the AA group (RR 1.47, 95% CI 1.01-2.15, P = 0.046). AA was associated with a longer duration of hospital stay compared to 4F-PCC (mean difference [MD] 0.64, 95% CI 0.07-1.22, P = 0.03). Neither a significant difference in length of intensive care unit stay (MD 0.25, 95% CI - 0.36 to 0.86, P = 0.41) nor a significant difference in hematoma volume expansion was reported (MD - 0.89, 95% CI - 3.11 to 1.34, P = 0.435). Our results suggest that AA is superior to 4F-PCC in enhancing the hemostatic efficacy and reducing the overall and in-hospital mortality rates. More thromboembolic events are thought to be associated with the use of AA. However, more studies are required to validate whether the better results of AA in improving hemostatic efficacy are enough to make up for their higher cost and their possible risk of thromboembolic events.

Optimizing warfarin and dual oral anticoagulation practices in an academic clinic during a merger amid the COVID-19 pandemic in a marginalized population

BACKGROUND

The closure of a pharmacy-led anticoagulation clinic, which provided point-of-care (POC) international normalized ratio (INR) testing and face-to-face visits, coupled with the transition to an academic physician-led clinic without POC INR testing and reliance on telephone communication, created significant challenges for warfarin management during the Coronavirus disease 2019 pandemic. The aim of this quality control project was to increase the percentage of patients on warfarin within the optimal time in therapeutic range (TTR) from 52.30% to 65.00%, sustain baseline quarterly cumulative percentage TTR to 59.00%, and transition 20% of eligible patients from warfarin to dual oral anticoagulation (DOAC) within 12 months.

METHODS

A multidisciplinary team employed a Fishbone diagram, stakeholder analysis, process flow map, and a driver diagram. Significant barriers included knowledge gaps, fear of blood draws, lack of POC INR testing, and noninteroperable electronic health records (EHRs). Primary outcome measures included quarterly cumulative percentage TTR, 2-monthly percentage TTR, and the percentage of eligible patients switched to DOAC. Process measures included INR completion rates. Key interventions involved educating patients and the care team, transitioning patients to DOAC, improving EHRs, and optimizing processes. Data analysis utilized run charts.

RESULTS

Monthly INR completion rates rose from 63% to 87% within 12 months and reached 92% during the 6 months post-project period. Among 143 patients, 40.55% (58) were eligible for a DOAC switch, with 51.72% (30/58) successfully transitioning during the project and the 6-month post-project period. Two-monthly TTR rates improved from the baseline of 52.30% to 62.00% during the study period and remained sustainable at 62.80% in the post-project phase. Quarterly cumulative TTR rates remained stable at 59.20% during the study period in 2021. The quarterly cumulative TTR rates continued to increase at 60.50% and 64.40% in 2022 and 2023, respectively, during the post-project period. No bleeding episodes occurred during the 15-month post-project period.

CONCLUSION

Multi-faceted strategies significantly improved warfarin safety during the project and maintained these improvements for 24 months. Transitioning from warfarin to DOACs was crucial for optimizing anticoagulation management with limited resources. The lead physician and team used various tools to address barriers to effective warfarin management, ensure appropriate DOAC prescribing, and enhance practices for DOAC prescriptions. This project effectively addressed barriers, improved population health, and provided a model for anticoagulation management in primary care settings.

Transitioning between therapeutic anticoagulants: a clinicians guide to switching patients to or from DOAC therapy

INTRODUCTION

The transition to or from direct oral anticoagulants (DOACs) is common in clinical practice.

AREAS COVERED

A literature search was conducted on PubMed, Google Scholar, and UpToDate up to March 2024 for conditions and approaches for transitioning from one agent to the other. No randomized clinical trials were retrieved except for two studies regarding switching to DOAC in well-conducted vitamin K antagonist (VKA) therapy. A narrative review was conducted addressing the conditions for switching from one agent to the other, such as thromboembolic events and major bleeding during anticoagulation, development or worsening of kidney or liver failure, initiation of interfering drugs, adverse events such as allergic reactions, frailty, patients' preferences, and affordability. During transitions from one anticoagulant to the other, the risk of both thromboembolic and bleeding complications should be minimized. The current approaches for such transitions are derived from those employed in clinical trials evaluating DOAC and from product information.

EXPERT OPINION

Many uncertainties remain regarding those circumstances requiring a change in anticoagulant strategies, as they lack evidence-based guidance. It can be envisaged that the problem of switching to and from DOAC will need additional studies especially addressing the conditions and the best approach to such transitions.

Anticoagulant Therapy in Patients Undergoing Acute Pulmonary Embolism Interventions

Catheter-based interventions and surgical embolectomy represent alternatives to systemic fibrinolysis for patients with high-risk pulmonary embolism (PE) or those with intermediate-high-risk PE who deteriorate hemodynamically. They are indicated when systemic fibrinolysis is contraindicated or ineffective, or if obstructive shock is imminent. Extracorporeal membrane oxygenation can be added to reperfusion therapies or used alone for severe right ventricular dysfunction and cardiogenic shock. These advanced therapies complement but do not replace anticoagulation, which remains the cornerstone in PE management. This review summarizes the evidence and shares practical recommendations for the use of anticoagulant therapy before, during, and after acute PE interventions.

DOAC-Remove to counteract the interference of anti-Xa oral anticoagulants on the monitoring of heparin

INTRODUCTION

The monitoring of unfractionated heparin (UFH) by anti-factor Xa activity (AXA) is commonly used to ensure effective anticoagulation and prevent bleeding risk. However, in patients previously treated with an anti-Xa direct oral anticoagulant (DOAC) switching to UFH therapy, there is a risk of interference that may lead to inappropriate anticoagulation. The first objective of this study was to validate DOAC-Remove to remove DOAC for measuring UFH specific AXA. The second objective was to assess the length of DOAC interference on UFH monitoring and to identify potential predictive factors.

MATERIALS AND METHODS

This monocentric retrospective study included all patients admitted from April 2019 to April 2021 previously treated with anti-Xa DOAC, and for whom an interference on UFH monitoring was suspected. Interference was defined as a difference in the AXA measured before and after using DOAC-Remove >2.8-fold standard deviation of the method.

RESULTS

Removal with DOAC-Remove was specific of DOAC (apixaban n = 42, rivaroxaban n = 41, UFH n = 20) and sufficient to avoid interference on UFH AXA measurement. The exact interference length was 6.0 days [IQR 3.0-11.0] for apixaban (n = 26) and 4.5 days [IQR 2.0-5.8] for rivaroxaban (n = 20). Among the 89 patients sorted based on an interference length ≤ or >3 days, 74 (83.1%) presented an interference greater than 3 days. Correlations were observed with age for apixaban and creatinine for rivaroxaban.

CONCLUSIONS

Our results suggest that DOAC-Remove could be of high interest in patients receiving UFH previously treated with an anti-Xa DOAC even if DOAC was stopped for more than 3 days.

Anticoagulation in Chronic Kidney Disease

The nuanced landscape of anticoagulation therapy in patients with chronic kidney disease (CKD) presents a formidable challenge, intricately balancing the dual hazards of hemorrhage and thrombosis. These patients find themselves in a precarious position, teetering on the edge of these risks due to compromised platelet functionality and systemic disturbances within their coagulation frameworks. The management of such patients necessitates a meticulous approach to dosing adjustments and vigilant monitoring to navigate the perilous waters of anticoagulant therapy. This is especially critical considering the altered pharmacokinetics in CKD, where the clearance of drugs is significantly impeded, heightening the risk of accumulation and adverse effects. In the evolving narrative of anticoagulation therapy, the introduction of direct oral anticoagulants (DOACs) has heralded a new era, offering a glimmer of hope for those navigating the complexities of CKD. These agents, with their promise of easier management and a reduced need for monitoring, have begun to reshape the contours of care, particularly for patients not yet on dialysis. However, this is not without its caveats. The application of DOACs in the context of advanced CKD remains a largely uncharted territory, necessitating a cautious exploration to unearth their true potential and limitations. Moreover, the advent of innovative strategies such as left atrial appendage occlusion (LAAO) underscores the dynamic nature of anticoagulation therapy, potentially offering a tailored solution for those at the intersection of CKD and elevated stroke risk. Yet the journey toward integrating such advancements into standard practice is laden with unanswered questions, demanding rigorous investigation to illuminate their efficacy and safety across the spectrum of kidney disease. In summary, the management of anticoagulation in CKD is a delicate dance, requiring a harmonious blend of precision, caution, and innovation. As we venture further into this complex domain, we must build upon our current understanding, embracing both emerging therapies and the need for ongoing research. Only then can we hope to offer our patients a path that navigates the narrow strait between bleeding and clotting, toward safer and more effective care.

Modelling the effects of 4-factor prothrombin complex concentrate for the management of factor Xa-associated bleeding

The management of factor Xa (FXa) inhibitor-associated bleeding remains a clinical challenge. Massive bleeding is often associated with complex coagulopathy and, thus, the sole reversal of FXa inhibitors might not be sufficient to restore hemostasis, requiring instead a multimodal approach. Four-factor prothrombin complex concentrate (4F-PCC) is widely recognized as a viable treatment option for FXa inhibitor-associated bleeding. Here, we applied computational models to explore the effect 4F-PCC has on the coagulation cascade and restoration of thrombin generation in a system that simulates a patient that has received a FXa inhibitor. The coagulation model is largely based on a previously developed model with modifications incorporated from various other published sources. The model was calibrated and validated using data from a phase 3 clinical trial of vitamin K antagonist reversal with 4F-PCC. Using the parameters and initial conditions determined during the calibration and validation process, the prothrombin time (PT) test simulations predicted a PT of 11.4 seconds. The model successfully simulated the effects of rivaroxaban and apixaban on total thrombin concentration and showed that 4F-PCC increased thrombin generation in the presence of rivaroxaban or apixaban.

Guidelines on deep vein thrombosis of the Brazilian Society of Angiology and Vascular Surgery

Deep vein thrombosis is one of the main causes of inpatient and outpatient morbidity, both in medical and surgical patients, significantly impacting mortality statistics and requiring prompt diagnosis so that treatment can be initiated immediately. This document was prepared and reviewed by 11 specialists certified by the Brazilian Society of Angiology and Vascular Surgery, who searched the main databases for the best evidence on the diagnostic (physical examination, imaging) and therapeutic approaches (heparin, coumarins, direct oral anticoagulants, fibrinolytics) to the disease.

Timing Matters: A Machine Learning Method for the Prioritization of Drug-Drug Interactions Through Signal Detection in the FDA Adverse Event Reporting System and Their Relationship with Time of Co-exposure

INTRODUCTION

Current drug-drug interaction (DDI) detection methods often miss the aspect of temporal plausibility, leading to false-positive disproportionality signals in spontaneous reporting system (SRS) databases.

OBJECTIVE

This study aims to develop a method for detecting and prioritizing temporally plausible disproportionality signals of DDIs in SRS databases by incorporating co-exposure time in disproportionality analysis.

METHODS

The method was tested in the Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS). The CRESCENDDI dataset of positive controls served as the primary source of true-positive DDIs. Disproportionality analysis was performed considering the time of co-exposure. Temporal plausibility was assessed using the flex point of cumulative reporting of disproportionality signals. Potential confounders were identified using a machine learning method (i.e. Lasso regression).

RESULTS

Disproportionality analysis was conducted on 122 triplets with more than three cases, resulting in the prioritization of 61 disproportionality signals (50.0%) involving 13 adverse events, with 61.5% of these included in the European Medicine Agency's (EMA's) Important Medical Event (IME) list. A total of 27 signals (44.3%) had at least ten cases reporting the triplet of interest, and most of them (n = 19; 70.4%) were temporally plausible. The retrieved confounders were mainly other concomitant drugs.

CONCLUSIONS

Our method was able to prioritize disproportionality signals with temporal plausibility. This finding suggests a potential for our method in pinpointing signals that are more likely to be furtherly validated.

Assessment of Temporary Warfarin Reversal in Patients With Left Ventricular Assist Devices: the KVAD Study

BACKGROUND

Patients with left ventricular assist devices (LVADs) require interruption of warfarin for invasive procedures, but parenteral bridging is associated with many complications. Four-factor prothrombin complex concentrate (4F-PCC) can temporarily restore hemostasis in patients undergoing anticoagulation with warfarin.

OBJECTIVES

This pilot study evaluated the strategy of using variable-dose 4F-PCC to immediately and temporarily reverse warfarin before invasive procedures without holding warfarin in patients with LVADs. The duration of effect of 4F-PCC on factor levels and time to reestablish therapeutic anticoagulation post procedure were assessed.

METHODS

Adult patients with LVADs and planned invasive procedures were enrolled from a single center. Warfarin was continued uninterrupted. The 4F-PCC dose administered immediately pre-procedure was based on study protocol. International normalized ratio (INR)- and vitamin K-dependent factor levels were collected before and during the 48 hours after 4F-PCC administration. The use of parenteral bridging, International Society for Thrombosis and Haemostasis major and clinically relevant nonmajor bleeding (CRNMB) and thromboembolic events at 7 and 30 days were collected.

RESULTS

In 21 episodes of 4F-PCC reversal, median baseline INR was 2.7 (IQR 2.2-3.2). The median dosage of 4F-PCC administered was 1794 units (IQR 1536-2130). At 24 and 48 hours post 4F-PCC administration, median INRs were 1.8 (IQR 1.7-2.0) and 2.0 (IQR 1.9-2.4). Two patients required postoperative bridging. One patient experienced major bleeding within 72 hours, and 2 experienced CRNMB within 30 days. There were no thromboembolic events. Baseline and post 4F-PCC vitamin K-dependent factor levels corresponded with changes in INR values. The median time to achieve therapeutic INR post-procedure was 2.5 days (IQR, 1-4).

CONCLUSION

Administration of 4F-PCC for temporary reversal of warfarin for invasive procedures in patients with LVADs allowed for continued warfarin dosing with minimal use of post-intervention bridging, limited bleeding and no thromboembolic events.

Advances in the medical treatment and diagnosis of intracranial hemorrhage associated with oral anticoagulation

INTRODUCTION

With the increasing prevalence of atrial fibrillation (AF), it entails expanding oral anticoagulants (OACs) use, carrying a higher risk of associated hemorrhagic events, including intracranial hemorrhage (ICH). Despite advances in OACs development with a better safety profile and reversal agent for these anticoagulants, there is still no consensus on the optimal management of patients with OACs-associated ICH.

AREAS COVERED

In this review, the authors have carried out an exhaustive search on the advances in recent years. The authors provide an update on the management of ICH in anticoagulated patients, as well as an update on the latest evidence on anticoagulation resumption, recent therapeutic strategies, and investigational drugs that could play a role in the future.

EXPERT OPINION

Following an ICH event in an anticoagulated patient, a comprehensive clinical evaluation is imperative. Anticoagulation should be promptly withdrawn and reversed. Once the patient is stabilized, a reintroduction of anticoagulation should be considered, typically within a timeframe of 4-8 weeks, if feasible. If re-anticoagulation is not possible, alternative options such as Left Atrial Appendage Occlusion are available.

Anticoagulation and compression therapy for proximal acute deep vein thrombosis

The treatment of proximal deep vein thrombosis (DVT) of the lower limbs includes an initial management phase, covering the first 1 to 3 weeks, a primary treatment phase, lasting a minimum of 3 months, and a secondary treatment phase for those patients requiring continuing anticoagulation beyond the first 3 to 6 months. During the initial phase most patients with DVT can be managed as outpatients. Exclusion criteria for home treatment include high risk of bleeding, limb threatening DVT or other conditions requiring hospitalisation. Anticoagulant drugs represent the mainstay of treatment and include parenteral drugs such as unfractionated heparin or low molecular weight heparin, and oral drugs such as the vitamin K antagonists and the direct oral anticoagulants (DOACs). DOACs are currently recommended as the first line of treatment for proximal DVT of the lower limbs, with no preference for one DOAC over another. Factors to consider when choosing the anticoagulant strategy include, among others, renal and liver function, underlying diseases such as cancer or the antiphospholipid syndrome, and patient preferences. Indefinite duration of anticoagulation beyond the first 3 to 6 months is recommended for patients with unprovoked DVT and patients with permanent, chronic risk factors. Two DOACs, namely apixaban and rivaroxaban, can be administered at low doses for the secondary prevention of DVT. Elastic compression stockings (ECS) have been used for decades in patients with proximal DVT with the aim of counteracting the venous hypertension generated by the vascular disorder and reducing leg edema and to prevent the post-thrombotic syndrome.

Unresolved questions on venous thromboembolic disease. Venous thromboembolism (VTE) management in obese patients. Consensus statement of the French Society of Vascular Medicine (SFMV)

Obesity is an alarming worldwide public health issue and is defined as a body mass index (BMI) of 30kg/m2 or more. It is considered as a risk factor for first thrombotic event and is associated with a significant risk of recurrence. Consequently, obese patients are often treated by anticoagulant therapy but data from randomised control trial are scarce. We will review in this narrative review the state of the art of the prescription of anticoagulant for the prevention and treatment of venous thromboembolism (VTE) in obese patients.

Temporal Changes in Long-Term Outcomes of Venous Thromboembolism From the Warfarin Era to the Direct Oral Anticoagulant Era

BACKGROUND

There have been limited data on the changes in clinical outcomes after the introduction of direct oral anticoagulants (DOACs) for venous thromboembolism (VTE) in real clinical practice. We evaluated the changes in management strategies and long-term outcomes from the warfarin era to the DOAC era.

METHODS AND RESULTS

We compared the 2 series of multicenter COMMAND VTE (Contemporary Management and Outcomes in Patients With Venous Thromboembolism) registries in Japan enrolling consecutive patients with acute symptomatic VTE: Registry 1: 3027 patients in the warfarin era (2010-2014) and Registry 2: 5197 patients in the DOAC era (2015-2020). The prevalence of DOAC use increased more in Registry 2 than in the Registry 1 (Registry 1: 2.6% versus Registry 2: 79%, P<0.001). The cumulative 5-year incidence of recurrent VTE was significantly lower in Registry 2 than in Registry 1 (10.5% versus 9.5%, P=0.02), and the risk reduction of recurrent VTE in Registry 2 remained significant even after adjusting the confounders (hazard ratio [HR], 0.78 [95% CI, 0.65-0.93]; P=0.005). The cumulative 5-year incidence of major bleeding was not significantly different between the 2 registries (12.1% versus 13.7%, P=0.26), and the risk of major bleeding between the 2 registries was not significantly different even after adjusting the confounders (HR, 1.04 [95% CI, 0.89-1.21]; P=0.63).

CONCLUSIONS

Along with the shift from warfarin to DOACs, there was a lower risk of recurrent VTE in the DOAC era than in the warfarin era, whereas there was no apparent change in the risk of major bleeding, which might still be an unmet need even in the DOAC era.

Co-administration of Four-Factor Prothrombin Complex Concentrate With Andexanet alfa for Reversal of Nontraumatic Intracranial Hemorrhage

Objective: Andexanet alfa is approved for the reversal of life-threatening or uncontrolled bleeding due to factor-Xa inhibitors. Data are limited on outcomes for patients who receive both andexanet alfa and 4-factor prothrombin complex concentrate (4F-PCC). The aim of this case series is to evaluate the safety and efficacy outcomes in patients receiving the two agents in combination. Methods: Electronic medical records of patients who received both 4F-PCC and andexanet alfa for nontraumatic intracranial hemorrhage from January 2019 to March 2022 were retrospectively reviewed. Hemostatic efficacy and complications related to concurrent use of 4F-PCC with andexanet alfa were documented. Results: Nine patients received 4F-PCC and andexanet alfa for reversal of factor Xa inhibitor-associated intracranial bleeding, eight of whom required reversal of apixaban. Of these nine patients, five patients died within 28 days for a 56% incidence of mortality. The average time from 4F-PCC administration to andexanet alfa administration was 3 hours and 9 minutes. Most doses of andexanet alfa were given for concern for bleed expansion after 4F-PCC administration. Hemostatic efficacy based on stability of repeat computed tomography scans post-administration of both agents was found in six patients (66.67%), with a 55.56% n incidence of thromboembolism, including two pulmonary embolisms, two deep vein thromboses, and one renal artery thrombosis. Conclusion: Risks and benefits should be weighed to determine if there is benefit to adding andexanet alfa to 4F-PCC in patients with incomplete hemostasis and life-threatening hemorrhage. The combination of andexanet alfa and 4F-PCC may increase the risk of thrombotic complications without improving mortality.

Vitamin K Antagonist Reversal for Urgent Surgery Using 4-Factor Prothrombin Complex Concentrates: A Randomized Clinical Trial

Importance

Millions of people take vitamin K antagonists (VKAs). Some people who need urgent surgical procedures require rapid VKA reversal to prevent excessive intraoperative bleeding.

Objective

To evaluate the hemostatic noninferiority of an investigational 4-factor prothrombin complex concentrate (4F-PCC) to a control 4F-PCC for rapid VKA reversal before urgent surgery.

Design, Setting, and Participants

This phase 3, double-blind, noninferiority randomized clinical trial (LEX-209) was conducted in 24 hospitals in the US, Russia, Georgia, Belarus, Ukraine, and Romania from June 7, 2017, through November 8, 2021; the study was stopped in February 2022. Participants were adult patients taking VKA who had an international normalized ratio (INR) of 2 or higher and needed urgent surgery with a substantial bleeding risk (≥50 mL). Patients were randomized 1:1 to a single infusion of either the investigational 4F-PCC or the control 4F-PCC. Data analysis followed intention-to-treat and per-protocol approaches.

Interventions

Single intravenous infusion was dosed by body weight and baseline INR. A dose of 25, 35, or 50 IU/kg of investigational 4F-PCC or control 4F-PCC was administered for baseline INR of 2 to less than 4, 4 to 6, or over 6, respectively.

Main Outcome and Measure

The primary end point was hemostatic efficacy at surgery end. An independent adjudication board, blinded to the 4F-PCC treatment allocation, assessed hemostatic efficacy using an objective 4-point scale.

Results

A total of 208 patients (median [range] age, 67.5 [31-92] years; 118 males [56.7%]) received the investigational (n = 105) or the control (n = 103) 4F-PCC. The median (range) dose was 25 (16-50) IU/kg in the investigational group and 25 (15-50) IU/kg in the control group, with a median (range) infusion time of 12 (8-50) minutes and 13 (7-30) minutes and a median (range) time from infusion to surgery start of 1.42 (0.25-15.25) hours and 1.50 (0.42-18.50) hours, respectively. Baseline median (range) INR was 3.05 (1.97-21.10) in the investigational group and 3.00 (2.00-11.30) in the control group. In the intention-to-treat analysis, the investigational 4F-PCC was noninferior to the control 4F-PCC, resulting in effective hemostasis in 94.3% of patients vs 94.2% of patients (proportion difference, 0.001; 95% CI, -0.080 to 0.082; P < .001), meeting the prespecified noninferiority margin of 0.15. An INR of 1.5 or lower at 30 minutes after infusion occurred in 78.1% of patients in the investigational group vs 71.8% of patients in the control group (proportion difference, 0.063; 95% CI, -0.056 to 0.181). Thrombotic events (2.9% vs 0%, respectively) and mortality (4.8% vs 1.0%, respectively) were no different than expected for 4F-PCC use. One patient in each treatment group discontinued due to adverse events (cardiac disorders unrelated to 4F-PCC).

Conclusions and Relevance

This randomized clinical trial found that the investigational 4F-PCC was hemostatically noninferior to the control 4F-PCC for rapid VKA reversal in patients needing urgent surgery with considerable bleeding risk; the safety profile of these two 4F-PCCs was similar. These results support the investigational 4F-PCC as a therapeutic option for surgical patients requiring rapid VKA reversal.

Trial Registration

ClinicalTrials.gov Identifier: NCT02740335.

Apixaban versus low molecular weight heparin in patients with cancer-associated venous thromboembolism: a systematic review and meta-analysis

Background

The optimal treatment regimen for patients with cancer-associated venous thromboembolism (CA-VTE) remains unclear. Therefore, the authors sought to compare the outcomes of (VKAs) versus direct apixaban and low molecular weight heparin (LMWH) in patients with CA-VTE.

Methods

MEDLINE, Embase, and Cochrane Central databases were searched for randomized controlled trials (RCTs) and observational studies comparing the efficacy and safety of apixaban and LMWH in patients with CA-VTE. Major bleeding, clinically relevant non-major bleeding (CRNMB), recurrence of pulmonary embolism (PE), deep venous thrombosis (DVT) and bleeding-related mortality were among outcomes of interest. Mantel-Haenszel weighted random-effects model was used to calculate relative risks (RRs) with 95% CIs.

Results

The analysis included 12 011 patients from 3 RCTs and 2 observational studies. Compared to LMWH, apixaban significantly decreased the risk of major bleeding [RR 0.67 (95% CI 0.54, 0.83); P=0.0003, I2=0%] without significantly changing the risk of clinically relevant non-major bleeding [RR 0.96 (95% CI 0.64, 0.1.45); P=0.85, I2=57%]. Patients on apixaban had a noticeably reduced the risk of recurrence of PE than those taking LMWH, according to a meta-analysis [RR 0.56 (95% CI 0.32, 0.99); P=0.05, I2=0%]. There was no discernible difference between apixaban and LMWH in bleeding-related mortality events [RR 0.20 (95% CI 0.01, 4.18); P=0.30, I2=NA%], and recurrence of DVT [RR 0.60 (95% CI 0.22, 1.59); P=0.23, I2=32%].

Conclusion

Due to its lower risk of severe bleeding and reduced PE recurrence, apixaban may be a preferable treatment option for CA-VTE, but additional research is required to validate these conclusions and evaluate its long-term efficacy and safety.

Poor patients' knowledge about venous thromboembolism and its therapy is associated with increased risk of major bleeding and discontinuation of anticoagulation: A cohort study

It has been shown that patients' knowledge about venous thromboembolism (VTE) and its therapy is suboptimal, which might reduce compliance and worsen prognosis. We investigated whether low VTE patients' knowledge affects their clinical outcomes during long-term follow-up. We evaluated 151 consecutive patients (51.8 ± 15.7 years) after unprovoked VTE, who were recruited from the outpatient clinic (Krakow, Poland). All patients received anticoagulant treatment, mostly with direct oral anticoagulants (n = 113, 74.8%). The modified Jessa Atrial fibrillation Knowledge Questionnaire (JAKQ-VTE; 16 questions) was used to assess the knowledge of VTE and anticoagulant therapy. During a median follow-up of 58.0 months, VTE recurrence, major bleeding, and anticoagulation withdrawal were recorded. The median percentage of correct responses was 62.5% (12.5-100%) and was inversely correlated with age (P < .01). Diabetic patients and those with positive family history of VTE had lower overall scoring compared to the remainder (both P < .05). Major bleeding (n = 10, 6.6%) and anticoagulation withdrawal (n = 28, 18.5%), but not VTE recurrence (n = 12, 7.9%), were associated with lower overall scoring compared to the remainder (48.8% ± 12.5% vs 63.8% ± 16.3%, P = .003 and 55.3% ± 14.7% vs 64.4% ± 16.3%, P = .040, respectively). Major bleeding was independently associated with the female sex (hazard ratio [HR] 6.18; 95% confidence interval [CI] 1.15-33.19, P = .034), younger age (HR per 10 years 0.55; 95% CI 0.34-0.90, P = .016), OAC therapy discontinuation (HR 6.69; 95% CI 1.62-27.70), and lower overall scoring of JAKQ-VTE (HR 0.60 per 10 percentage points; 95% CI 0.40-0.92, P = .019). Insufficient knowledge about VTE and anticoagulant treatment predisposes to a higher risk of major bleeding and therapy discontinuation, but not VTE recurrence in unprovoked VTE patients during long-term follow-up.